/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package vip.zhenzicheng.rocketmq.api.quickstart;

import org.apache.rocketmq.client.consumer.DefaultMQPushConsumer;
import org.apache.rocketmq.client.consumer.listener.ConsumeConcurrentlyContext;
import org.apache.rocketmq.client.consumer.listener.ConsumeConcurrentlyStatus;
import org.apache.rocketmq.client.consumer.listener.MessageListenerConcurrently;
import org.apache.rocketmq.client.exception.MQClientException;
import org.apache.rocketmq.common.consumer.ConsumeFromWhere;
import org.apache.rocketmq.common.message.MessageExt;
import vip.zhenzicheng.rocketmq.api.RocketMQConstant;

import java.util.List;

/**
 * This example shows how to subscribe and consume messages using providing {@link DefaultMQPushConsumer}.
 */
public class Consumer {

  public static void main(String[] args) throws InterruptedException, MQClientException {

    /*
     * Instantiate with specified consumer group name.
     */
    DefaultMQPushConsumer consumer = new DefaultMQPushConsumer("please_rename_unique_group_name_4");

    /*
     * Specify name server addresses.
     * <p/>
     *
     * Alternatively, you may specify name server addresses via exporting environmental variable: NAMESRV_ADDR
     * <pre>
     * {@code
     * consumer.setNamesrvAddr("name-server1-ip:9876;name-server2-ip:9876");
     * }
     * </pre>
     */
    consumer.setNamesrvAddr(RocketMQConstant.DEFAULT_ROCKET_IP);
    /*
     * Specify where to start in case the specified consumer group is a brand new one.
     */
    consumer.setConsumeFromWhere(ConsumeFromWhere.CONSUME_FROM_LAST_OFFSET);

    /*
     * Subscribe one more more topics to consume.
     */
    consumer.subscribe("TopicTest", "*");

    /*
     *  Register callback to execute on arrival of messages fetched from brokers.
     */
    consumer.registerMessageListener(new MessageListenerConcurrently() {

      @Override
      public ConsumeConcurrentlyStatus consumeMessage(List<MessageExt> msgs,
                                                      ConsumeConcurrentlyContext context) {
        System.out.printf("%s Receive New Messages: %s %n", Thread.currentThread().getName(), msgs);
        return ConsumeConcurrentlyStatus.CONSUME_SUCCESS;
      }
    });

    /*
     *  Launch the consumer instance.
     */
    consumer.start();

    System.out.printf("Consumer Started.%n");
  }
}
